The Covid-19 traffic light system is almost certain to be scrapped by Cabinet today and the change could come into effect as soon as midnight tonight, barring major developments or a last-minute change of heart.

It is understood the decision being put to Cabinet to sign off on is to drop the traffic light system and its rules almost immediately, and to let one of the key Covid-19 provisions allowing the Government to make rules for Covid-19 lapse rather than renew it.

The Covid-19 Protection Framework (known as the traffic light system), including masking rules, would be gone but masking requirements in some sectors, such as health care, are expected to be retained.

Otherwise it would be up to businesses and individual organisations to decide whether and when to adopt mask policies.

On Newstalk ZB this morning, Deputy Prime Minister Grant Robertson said there would "absolutely" be clarity about the Covid rules after Cabinet met. He said Cabinet would look at the health advice and the broader economic assessment and make its decisions.

"This is still a virus that's infecting a lot of people but because of our high levels of vaccination, because people have by and large stuck to the rules around things like isolation and mask wearing we've done well. But our approach has been tweaked and changed all the way through in response to things to be proportionate, and so Cabinet will look at that today and make our decision.

"We have to plan for variants into the future but we also have to acknowledge that through winter our health system came under a lot of strain but we made it through.

"But we've just to make sure that we've got a fit for purpose response to the place we find ourselves in now.

"Obviously Covid has this ability to not respect the foreseeable future as a concept, but clearly we want New Zealanders to be able to know exactly what is expected of them."

The NZ Herald revealed last Thursday that Cabinet was expected to decide on scrapping the traffic lights altogether rather than changing the rules or moving to green. At that stage advice was still coming in and the timing of the announcements was not set.

• 'Dump it' – Seymour calls for code scanning, MIQ, mandates to be axed
• Barry Soper: It would seem that mandates and vaccine passes are on their way out

The traffic light system was set up under the Epidemic Preparedness (COVID-19) Notice 2020 which has been renewed by the Prime Minister every three months since March 2020. The Notice is required to be able to make orders for the Covid-19 response.

That was last renewed in June and is due to expire on September 16 unless renewed again this week – something that is usually done a few days in advance.

As yet, it has not been renewed – it requires the PM to consult with the Minister of Health and the director-general of health and provide an assurance that she is satisfied "the effects of the outbreak of COVID-19 are likely to disrupt or continue to disrupt essential governmental and business activity in New Zealand significantly".

In the event of a major development with Covid-19, the Government still has the ability to re-introduce measures – the main COVID-19 Public Health Response Act 2020 was renewed in June to stay in force until at least December, unless repealed earlier.

However, the Government is working on a less heavy-handed Covid-19 response and the overall pandemic response to guide the management of it in the future.

Act leader David Seymour has called for measures such as isolation periods to be dropped. He said they were among the strictest in the world.

"No other jurisdiction requires seven days mandatory isolation for cases and household contacts. Jacinda Ardern needs to look to the rest of the world and change what are currently the world's most inflexible isolation rules."